NBS Source


Sikafloor® 21 PurCem is a three component, water based, medium strength, coloured polyurethane screed with self-smoothing properties. For use in areas of medium loading, abrasion and chemical exposure.

Suitable areas of application:

  • Food process plants.
  • Warehouses.
  • Chemical plants.
  • Pharmaceutical plants.
  • Power plants.
  • Storage areas.
  • Plant rooms.
  • Processing areas.
  • Laboratories.
  • Workshops.
  • Cold stores.


The cementitious substrate should be sound and of sufficient compressive strength (minimum 25 N/ mm²) and pull off strength (minimum 1.5 N/mm²). The surfaces must be dry and free of all contaminants, e.g. oils, grease, surface treatments and coatings, etc. The substrate must be prepared mechanically to achieve an open textured fine gripping surface, free of cement laitance. Weak concrete should be removed and surface defects such as blowholes and voids must be fully exposed. All dust, loose and friable material must be completely removed, preferably by brush and vacuum, from all surfaces before application of the coating. Repairs to cementitious substrates and filling of blowholes, levelling of irregularities, etc. should be carried out using an appropriate product from the SikaDur®, Sikafloor® or SikaGard® range of materials. Prior to application, confirm substrate moisture content. If >10% by weight, Sikafloor® EpoCem® may be applied as a DPM system.

General information

Specification data - Smoothing and levelling underlay compounds

Product Reference

Sikafloor® 21 PurCem

Resin flooring


Nominal thickness

4.5–6 mm

Surface finish/ treatment

Not required

Standard product features


Work with a trowel to the required levels, achieving a flat surface. Roll with spiked roller immediately (< 2 minutes).

Product Options


Refer to colour chart. Consult manufacturer for details.

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